Many types of input devices are presently available for performing operations in a computing system, such as buttons or keys, mice, trackballs, touch sensor panels, joysticks, touch screens and the like. Touch screens, in particular, are becoming increasingly popular because of their ease and versatility of operation as well as their declining price. Touch screens can include a touch sensor panel, which can be a clear panel with a touch-sensitive surface. The touch sensor panel can be positioned in front of a display screen so that the touch-sensitive surface covers the viewable area of the display screen. Touch screens can allow a user to make selections and move a cursor by simply touching the display screen via a finger or stylus. In general, the touch screen can recognize the touch and position of the touch on the display screen, and the computing system can interpret the touch and thereafter perform an action based on the touch event.
Touch sensor panels can be implemented as an array of pixels formed by multiple drive lines (e.g. rows) crossing over multiple sense lines (e.g. columns), where the drive and sense lines are separated by a dielectric material. An example of such a touch sensor panel is described in Applicant's co-pending U.S. application Ser. No. 11/650,049 entitled “Double-Sided Touch Sensitive Panel and Flex Circuit Bonding,” filed on Jan. 3, 2007, the contents of which are incorporated by reference herein. However, touch sensor panels having drive and sense lines formed on the bottom and top sides of a single substrate can be expensive to manufacture. One reason for this additional expense is that thin-film processing steps must be performed on both sides of the glass substrate, which requires protective measures for the processed side while the other side is being processed. Another reason is the cost of the flex circuit fabrication and bonding needed to connect to both sides of the substrate.